Cochlear Implants Help Overcome Noise Induced Hearing Loss

Permanent hearing loss can be caused by long, uninterrupted periods of constant exposure to excessive levels of noise.

PRLog - Sep. 29, 2011 - MANCHESTER, U.K. -- Permanent hearing loss can be caused by long, uninterrupted periods of constant exposure to excessive levels of noise. Almost, invariably, occurring within the heavy industrial or manufacturing workplace, industrial deafness, as it is commonly known, results in irreversible damage to the delicate hair cells within the cochlea of the inner ear.

Unless adequate ear defenders have been correctly worn, the likelihood is that a general deterioration over time will only be noticed when there’s an inability to clearly hear individual words of spoken conversation or there’s a constant need to turn up the television volume.

Alternatively, an acoustic shock or trauma can also cause serious irreparable hearing damage, such as a perforated eardrum, when an individual is exposed to a sudden, extremely loud noise, or a series of loud noises at close range. Call centre workers using headsets without limiters can often experience frequencies above 118dB.

Sometimes a hearing aid will not suffice to overcome severe noise induced hearing loss and around 10,000 people in the UK will fit cochlear implants instead. Whereas a hearing aid will amplify what the ear hears, the cochlear implants are electronic devices, which create the sensation of sound and will, instead, directly stimulate the auditory nerve, bypassing the ears and sending signals straight to the brain.

The implant comprises:

An internal receiver, which is surgically implanted into the mastoid bone behind the ear, with electrodes inserted into the cochlea part of the inner ear.

An external microphone and speech processor, which converts sound into an electrical signal sent to the electrodes in the inner ear to stimulate the auditory nerve and send a signal to the brain, where it is perceived as sound.

The aim of the cochlear implant is to provide access to the range of sounds that compose speech. This means having the ability to hear some sounds, but not to hear all the sounds that make up human speech. Depending on the individual, results can vary, ranging from hearing speech to just awareness of environmental sounds.

Although the sound heard with a cochlear implant is not the same as normal hearing, over time and with practice, performance ability will improve. Many cochlear implant users report being able to hear very well in quiet environments and also show significant hearing improvement in noisy environments.

Cochlear implants also enable deaf children to learn language, speak intelligibly and perform better at school. Adults are able to communicate more confidently, regain their independence, and improve employment prospects.